Investigating the initial steps in the biosynthesis of cyanobacterial sunscreen scytonemin.
The cyanobacterial natural product scytonemin (1) functions as a sunscreen, absorbing harmful UV-A radiation. Using information from a recently identified gene cluster, we propose a biosynthetic route to this pigment. We also report the characterization of two enzymes, NpR1275 and NpR1276, which are involved in the initial stages of this pathway. A regioselective acyloin reaction between indole-3-pyruvic acid (4) and p-hydroxyphenylpyruvic acid (5) is a key step in assembling the carbon framework of a proposed monomeric scytonemin precursor (2).
Balskus
Emily P
EP
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Walsh
Christopher T
CT
D002384:Catalysis; D002851:Chromatography, High Pressure Liquid; D000458:Cyanobacteria / Q000737:chemistry* / Q000378:metabolism*; D007211:Indoles / Q000737:chemistry* / Q000378:metabolism*; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry* / Q000378:metabolism*; D013473:Sunscreening Agents / Q000737:chemistry* / Q000378:metabolism*
D007211:Indoles; D010636:Phenols; D013473:Sunscreening Agents; C083368:scytonemin